Open-top refrigerated display case



Jan. 27, 3953 K. EN 2,626,508

OPEN-TOP REFRIGERATED DISPLAY CASE Filed Jan. 12, 1949 3 Sheets-Sheet 1oPEN Georg K. Eenf/y, BY 2 v a) 2 ATTORNEY-9 Jan. 27, 1953 G. K. BENTLYOPEN-TOP REFRIGERATED DISPLAY CASE 3 Sheets-Sheet 2 Filed Jan. 12, 1949QQZQ. 22:: 42 @QQQ INVENTOR. George A. fienf/y, @uwvZW A TORNEYS Jan.27, 11953 e. K. BENTLY OPEN-TOP REFRIGERATED DISPLAY CASE 3 Sheets-Sheet3 Filed Jan. 12, 1949 /I ll I/ l l/ 1/ x I AW BH U JNVENTOR. George KBer/fly, WZM

ATTORNEY! ?atented Jan. 27, 1953 OPEN-TOP REFRIGERATED DISPLAY CASEGeorge K. Bently, Kendallville, Ind., assignor to McCray RefrigeratorCompany, Inc., Kendallville, Ind., a corporation of Indiana ApplicationJanuary 12, 1949, Serial No. 70,555

7 Claims.

This invention relates to open-top refrigerated display cases of thetype used in food stores to display merchandise of a perishable nature.

The primary object of the invention is to improve on refrigerateddisplay cases of this character by effecting a more efficient anduniform cooling of produce with a less loss of cooled air to the outsideatmosphere than with the cases now generally used, and to accomplishthis in asimple and economical manner.

Other objects and advantages of the invention will be apparent from thefollowing detailed description, and from the accompanying drawingillustrating a preferred embodiment thereof, in which- Fig. l is a frontperspective view of a case embodying the invention; Fig. 2 is anenlarged section thereof on the line 2--2 in Fig. l, and Figs. 3 and 4are reduced sections taken on the lines 3-3 and 4-4, respectively, inFig. 2.

Referring to the drawings, I designates the front wall 2, 2 the opposingend walls, 3 the rear wall and 4 the bottom of the case body. The rearwall 3 extends above the level of the front wall, and is provided at itsupper end with a forwardly extending top 5 that is narrow in its forwardextension so as to provide a top access opening to the interior of thecase of considerable area between said top and the front wall of thecase. The front edge of the top 5- is provided with a downwardlyextending baffle 6 that is preferably but necessarily forwardlyinclined. A metal facing sheet I for the top extends forwardly adistance from the front edge of the top and then downwardly a shortdistance on a forward incline to form a front canopy 8 the full lengthof the top. A source 9 for directing a, light into the case is disposedunder the canopy 8 and preferably extends substantially the length ofthe case. The exposed front side of this canopy forms a price tag rail.

The front body wall I is considerably lower than both the rear wall 3and the end walls 2,2, and is extended to near the level of the frontend edges of the end walls by a front wall part In preferably of glass,so that the produce in the case may be viewed therethrough. The topedges of the end walls extend rearwardly on a slight incline to thelower front edge of the canopy 8. The baflle 6 extends down a distanceinto the case with its lower edge below the level of the high rear endportion of the ends 2,2, and preferably above the level of the top edgeof the front wall part Ill. In the present instance, the bottom edge ofsaid baflie is approximately half way between the top edge level of thepart II] and the bottom edge level of the canopy front.

The interior of the case is provided in its upper portion with anopen-top produce display chamber [2, the bottom of which is indicated atl3 and may comprise sheet metal sections that are removable to permitaccess to parts below and which rest at their rear end edges on a rearledge M and at their front end edges on a front ledge i5. The ledges l4and I5 are formed at the upper edges of rear and front verticalpartitions it and I1, respectively, which extend the full length of theinterior of the case with both partitions spaced from the respectiverear and front case walls.

The rear wall of the display chamber I2 is formed by a verticalpartition l8 extending upward from the rear edge of the ledge M to nearthe top 5 at the rear of the baffle 6 throughout the length of the caseand in forwardly spaced relation to the rear wall 3 to form a verticalflue Ill therebetween. This flue is divided lengthwise into a pluralityof sections by vertical webs 2i? serving as braces for the partition l8.These webs are provided with openings Zl for the free passage of airtherethrough.

The flue 19 at its lower end communicates with and is supplied with coolair from a distributing chamber 22. The upper end of the flue I9 ispreferably somewhat restricted by reason of the upper end portion of thepartition [8 being slightly rearwardly inclined at such point so thatthe discharge of air from the flue is upward under the top 5 and thenceforward and downward under the banle 6 into the top rear portion of thedisplay chamber I2. The air in its discharge from the flue into theinterior of the case is diffused and retarded to some extent by a screenor foramlnous partition 23 which extends rearwardly and downwardly fromthe baffle is a distance above its lower edge portion of the partitionl8. Upwardly beyond this point, the partition i8 is preferably formedwith a perforated or slotted extension lta which tends to furtherdiffuse and retard the air in its discharge from the flue 19 into thecase.

A partition 24 extends upward from the forward edge of the ledge [5 forthe entire length om case and in rearwardly spaced relation to the frontwall to form the flue 25 in the front portion of the case. The partition24, in the present instance, extends vertically to near the lower edgeof the front wall part l0 and then continues upward at a forwardincline, as shown at '26, to a short distance below the top of the wallpart l and in rearwardly spaced relation thereto to provide a narrowslot-like entrance 2! to the upper end of the flue 25. The parts 24 and26 of this partition, in the present instance, are shown as connected byan offset 28, and the part 26 is preferably of transparent glass topermit articles in the case to be viewed therethrough. A plurality ofbracket plates 29 are attached to the inner side of the front wall I andserve as supports and braces for the partitions 24 and 26.

The produce is supported in the case by a shelf 30 extending the entirelength of the display compartment I2 and slatted or perforated to permitthe circulation of air therethrough. The shelf 30 is preferably composedof a plurality of rectangular tray-like members placed side by side topermit any or all to be removed or vertically adjusted. These trays areadapted to be placed in various positions best suited to the display ofthe particular mechandise in hand and also for the selectivedistribution of cold air above and below the shelf, as hereinafterdescribed. For this purpose, the trays may be placed in differentvertically spaced horizontal positions a, b, or inclined upwardly andrearwardly from either of such positions, as shown at c, d, e and J inFig. 2, or the trays may rest on and be supported by either the bottoml3 or the ledges l4 and [5. In the a position, a tray is supported atits rear end by a ledge 32 on the front of the rear flue wall 18, and atits front end by releasable hooked engagement with the front partition24, as shown at 33. The trays may be tilted from this position to any ofthe positions c, d and e by raising their rear ends to be supported,respectively, by ledge brackets 34, 35 and 36 provided in superimposedrelation on the front side of the partition [8. When the trays are inthe raised horizontal position b they are supported at their rear endsby the ledge 34 and at their front ends by the hooked connection 3'!with the partition 24. The trays may be tilted from this position to theposition I by resting their rear ends on the ledge brackets 36. Ifdesired, the trays 30 may be removed and the produce supported by thebottom trays I3.

The partition [8 is provided lengthwise thereof between the ledges 32and 35 with a plurality of louvered openings 4l2- and also with similaropenings 4| and 42 between the ledges 34 and 35 and the ledges 35 and36, respectively. These openings direct air from the flue l9 forwardlyand downwardly into the compartment l2 below the shelf trays 30 when inany of their several positions, except, in the present instance, thebottom position a. These openings, or some of them, also serve to directair into the compartment above the trays when in the various positionsother than c and f.

The front partition 24, in the present instance below the tray positiona, is provided with a series of comparatively small openings 44 for theexit of air from the compartment [2 to the interior of the down flue 25.These openings combined with the inlet openings 21 for the flue 25 areof sufficient combined area to take care of the low pressure cold airadmitted to the compartment [2 through the various openings from theflue IS.

The flue 25 opens at its lower end into a plenum chamber 45 formed atits rear side by the partition I1, and this partition has an opening 4%;in its central portion through which a motor driven fan 4! drives theair rearwardly through a broad flue 48 having a restricted portion 49 atits rear end in which a cooling coil 50 is disposed to cause the airpassing therethrough to be cooled the desired extent. The rear end ofthe flue part 49 'wall 3 and partition l5.

opens into the air distributing chamber 22 in the lower portion of theflue l9. While the flue part 49 is restricted in width relative to thelength of the case, it is still of considerable width, as shown in Fig.3. The chamber 22 into which the flue 49 discharges is formed at its topand sides by a semicircular perforated or foramlnous baffle 51, whichcauses the air discharged into the chamber 22 to be trapped andpressurized and evenly distributed into the central and end portions ofthe flue 19. The bafile 5i is disposed between the rear TlllS is foundto be an important feature for the completely satisfactory operation ofa case constructed as shown.

In the operation of the case, air is drawn from the display compartmentl2 through the inlet openings 2'! and 43 to the flue 25 and thence tothe chamber 45 by the action of the fan 41, and is forced by the fanthrough the cooling coil fiue 49 and into the distributing chamber 22where it is pressurized and its flow restricted by the perforatedarcuate baffle 5|. This baflle causes the air to be distributeduniformly, vertically and sidewise into the bottom of the up flue [9 sothat the air flow throughout the entire horizontal length of the flue issubstantially equalized. Some of this air in its passage up the hue isdistributed to the chamber l2 through the louvered openings 40, 41 and42, with more or less of it passing under the merchandise supportingshelf 30, depending on the adjusted position of the shelf trays orsections except when resting on the bottom l3 or when in the lowerhorizontal position a. The louvers, which are above the shelf in anyposition of its adjustment, are designed to direct the discharging airdown onto the shelf and onto the produce supported thereby, while thosethat are below the shelf, which is in all positions except a, cause asupply of cold air to flow beneath the shelf, a portion of whichdischarges to the flue 25 through the openings 43 with the balancepassing up through the slatted or perforated shelf and around theproduce thereon. This manner of circulation causes distribution of coldair directly to the bottom of the produce so that its lower portion ismaintained at a substantially uniform temperature with its upper portionthat is cooled by the discharge of cold air into the upper portion ofthe chamber. This is an important feature, for in systems where the coldair passes either up or down, but not both, through the shelf andsupported merchandise, the air is warmed in its contact with themerchandise, so that the far side of the merchandise with respect to theair flow is necessarily warmer than the near side. This is especiallytrue with respect to large produce rticles or packages, such forinstance as meat, and may result in such a temperature differential inthe package that portions may not be maintained at a safe temperature toprevent spoilage or objectionable bacteria formation. The extent of coldair caused to be discharged below the shelf and to pass upwardtherethrough depends, of course, upon the adjusted position of the shelfand the number and extent of louver openings 4! and 42 that have theirdischarge below the shelf. The cold air that is discharged above theshelf through the louvered openings from the up or cold flue I9 isdirected downwardly against the produce on the shelf and flows slightlythereover to its point of discharge from the chamber through the outletflue opening 21. At the same time the stream of cold air dischargingfrom the top of the flue 19 under the battle -6, and the air risingthrough the shelf 30, commingle with the air discharging from thelouvered openings and passes therethrough into and down the dischargeflue 25. The air discharging from the flue i9 is at a relatively lowerpressure than that passing through the return flue 25.

The air discharging into the chamber l2 from the upper end of the fluel9 forms a blanket of cold air over the air discharging from thelouvered openings and compensates to a large extent for the heat takenup from the produce by such louver discharging air. This also protectsthe produce contacting air from the warmer outside air.

In practice, it is preferable to have the air discharge into the chamberi2 from the upper end of the flue l9 above the level of the top edge.

of the front wall part II]. It is also preferable to pull only a limitedquantity of air from the lower portion of the chamber l2 through thesmall openings 33 sufficient only to maintain a slow circulation throughthe area beneath the shelf with a considerable portion passing upthrough the shelf. The amount of refrigeration underneath the shelf isdetermined by the position of the shelf, and consequently the number ofeffective openings 40, 4| and 42 available for the purpose. Thus, araising of the shelf position increases such refrigeration and alowering decreases it. It is found in practice that no particularadvantage would be derived by controlling the discharge through theopenings 33 by use of a valve and for this reason no valve has beenshown. However, such a controlled discharge may be employed if desired.It is further found in practice that with the circulation as illustratedthe air is forced out of the top of the flue [9 at the back of thechamber 12 at low velocity, nd is taken in the narrow flue opening 2?near the top edge of the wall part it at high velocity, and that thisminimizes the amount of cold air spilled to the atmosphere and also theamount of warm air taken in from the outside.

I wish it understood that my invention is not limited to any specificconstruction, arrangement or form of the parts, as it is capable ofnumerous modifications and changes without departing from the spirit ofthe claims.

Having thus described my invention, what I claim as new, and desire tosecure by United States Letters Patent, is:

l. In an open-top refrigerated display case, a produce display chamber,a broad flue for directing cold air to said chamber, means for forcingcold air through said flue, and an arcuate perforated baiiie in theinlet end of the flue serving to pressurize and distribute the air invarious directions into the flue to render the air flow substantiallyuniform throughout the broad area of the flue.

2. In an open-top refrigerated display case, a produce display chamber,a broad vertical flue for directing cold air to said chamber, an arcuateperforated baffle forming an air distributing chamber in the lower endof said flue, said distributing chamber being of less width than saidflue and said bailie having its bowed side upward whereby air isdistributed upward and sideways therethrough to the flue, and means forcooling and forcefully discharging air into said distributing chamber.

3. In an open-top refrigerated display case having front, rear and endwalls, means within the case forming an open-top produce display chamberand vertical flues at the front and rear 6, sides thereof, the fluesbeing narrow from front to rear and substantially corresponding in widthto the horizontal length of the chamber, the rear flue having aplurality of vertically spaced rows of louvered openings directing airdownwardly therefrom into said chamber, and said front flue having itstop open to the chamber below the top of the front wall and having alower series .of openings for the inlet of air from the chamber, aproduce supporting shelf having provision for the passage of airtherethrough, means for supporting the front edges of the shelf abovesaid lower series of openings to the front flue, and a plurality ofvertically spaced supports at the front of said rear flue to selectivelysupport the rear edge of the shelf in different vertically spacedpositions to place a greater or less number of said rear louveredopenings below the shelf, and means below said chamber communicatingwith the lower ends of said flues and operable to create an up draftthrough said rear flue and a down draft through said front flue.

4. In an open-top refrigerated display case having front, rear and endwalls, means within the case forming an open-top produce display chamberand vertical flues at thefront and rear sides thereof, the flues beingnarrow from front to rear and substantially corresponding in width ,tothe horizontal length of the chamber, the rear flue having a pluralityof vertically spaced rows of louvered openings directing air downwardlytherefrom into said chamber and said front flue having its top open tothe chamber below the top of the front wall and having a lower series ofopenings for the inlet of air from the chamber, a produce supportingshelf having provision for the passage of air therethrough, means forsupporting the front edges of the shelf above said lower series ofopenings to the front flue and a plurality of vertically spaced supportsat the front of said rear flue to selectively support the rear edge ofthe shelf in different vertically spaced positions to place a greater orless number of said rear louvered openings below the shelf, meanscommunicating with the lower ends of said flues and operable to createan up draft through said rear flue and a down draft through said frontflue, and an arcuate perforated bafile in the inlet end of the rear flueto pressurize and distribute the air in various directions into the flueto render the air flow substantially uniform throughout the broad areaof the flue, said bafile disposed widthwise of the lower end portion ofthe rear flue and having its convex side upward and its concave sidedisposed toward and receiving the air from the said draft creatingmeans.

5. In an open-top refrigerated display case having front, rear and endwalls, means within the case forming a produce display chamber, a secondchamber therebelow and vertically disposed flues connecting saidchambers at the inner sides of two opposing walls of the displaychamber, one flue being for cold air and the other for relatively warmair, a shelf in said display chamber spaced from its bottom and havingopenings for the passage of air therethrough, said cold air flue havingprovision for discharging air therefrom into the display chamber at atleast one side of said shelf, and said other flue having provision bothbelow and above the shelf for the inlet of air thereto from the displaychamber, and means in said second chamber for drawing air from said warmair flue and cooling and forcing it through said cold air flue.

6. In an open-top refrigerated display case having front, rear and endwalls, means within thecase forming an upper produce display chamberancla lower chamber and vertically disposed lines at the innersides of twoopposing walls of the'upper chamber, oneflue being for cold air andlocated at the rear of the upper chamber and the other fiue beingior:relatively warmair, said cold air flue having openings for dischargingair into the rear. of said upper chamber, aproduce supporting. shelf insaid upper chamber vertically spaced relation to its :bottom and beingvertically adjustable relative to the discharge openingsin-said cold air.fiueto vary the amount of .cold air discharging into the chamber belowthe shelf, .saidlshelf having provision for the passage of air"therethrough'from the upper to the lower portion of .its chamber andsaid warm air flue having provision for the inlet of air thereto fromthe upperportion .of said upper chamber abovezthe shelf and alsofrom thelower 8 portion thereof below the shelf, and means in the lower chamberfor drawing air from said warm .air flue and cooling and forcing itthrough said cold air flue.

7. A combination as called for in claim 6 wherein the openings from thecold air flue are at different levels and some at least thereof arelouvered'to direct the discharging air downwardly into the upperchamber.

GEORGE K. BENTLY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED vSTATES PATENTS Number Name Date 2,223,761 Hall Dec. 3, 19402,447,759 MacMaster Aug. 24, 1948 20 2,463,614 Hardin Mar. 8, 19492,508,255 Hardin May 16, 1950

